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麻省理工的计算光子晶体的程序

MPB 1.4.2 (3/3/2003)

  * Interactive prompt is now "mpb>" not "guile>".

  * Output "freqs:" line lists headings as "k1, k2, k3" instead of
    "kx, ky, kz" since they are in reciprocal-lattice, not cartesian,
    coordinates.  Thanks to Theis Peter Hanson for the suggestion.

  * Bug fix in find-k for non-orthogonal lattices; thanks to Suxia
    (Susan) Yang for tracking down this bug.

  * Fixed SunOS problem where k vectors along no-size dimensions failed;
    thanks to Benjamin Cowan for the bug report.

  * Fixed find-k to work for band-min > 1; thanks to M. Povinelli for
    the bug report.

  * Fixed find-k to work for thunk band functions (which take no arguments
    and are called only once instead of per-band).

MPB 1.4.1 (9/16/2002)

  * Fixed NaN in field normalization when basis determinant was negative.
    Thanks to Rumen Iliew for the bug report.

  * Fixed compatibility problems with versions of Guile prior to 1.4.
    Thanks to Cazimir G. Bostan for bug reports.

  * Don't resize lattice basis for grid-size == 1 unless no-size was
    explicitly specified; thanks to Tairan Wang for the suggestion.

MPB 1.4 (9/12/2002)

  * New find-k routine to find k as a function of frequency, instead of
    vice-versa.

  * The Great Field Renormalization: all fields are now normalized
    to have unit *integral* of their energy density (instead of
    unit sum over the grid points), which is much more useful e.g. for
    perturbation theory.  (See field normalization section of manual.)

  * You can now save fields in Scheme variables to perform computations
    combining different fields.  Example routines, e.g. to output the
    Poynting vector, are included.

  * Functions to export (and import) the raw eigenvectors (planewave
    amplitudes), as well as to compute dot products of eigenvectors
    from different k-points (e.g. for detecting band crossings).

  * allow-negative-epsilon function to enable negative-dielectric support.

  * Added examples/dos.scm to compute density of states via simple
    Gaussian histogram, suggested by Xavier Gonze and Doug Allan.

  * Bug fix: allow real offdiagonal epsilon elements without requiring
    --with-hermitian-eps.  Thanks to Doug Allan for the bug report.

  * Eliminated floating-point error on Alpha for homogeneous structure.
    Thanks to F. Lopez-Tejeira for the bug report.

  * Added man page for mpb-split.

  * Minor installation fixes.

MPB 1.3 (3/10/2002)

  * You can now specify the grid size via the resolution input variable,
    instead of via grid-size.  In this case, you make e.g. a 2d simulation
    by creating a lattice with size no-size in one dimension.  The
    old syntax is still supported, but the new style is encouraged
    (all examples have been updated to the new style).

  * New functions to retrieve fields, dielectric functions, etcetera
    at any point, interpolated from the grid if necessary; see the
    get-*-point functions in the reference section.

  * New compute-field-integral function, analogous to compute-energy-integral;
    thanks to Marin Soljacic for the suggestion.

  * Support Scheme complex numbers where appropriate (e.g. in epsilon-offdiag
    or in the new field integration functions).

  * Got rid of NaN when computing the (undefined) group velocity
    for zero-frequency states at the Gamma point; arbitrarily
    return zero here instead.  Thanks to Dmitry N. Chigrin for
    reporting floating-point exceptions on Alphas.

  * Fixed compilation failure for Fortran compilers that use all upper case;
    thanks to Steve Lantz of Cornell.

  * Added "Fun with Fortran" section to installation manual describing
    common Fortran pitfalls; thanks to Steve Lantz for the suggestion.

  * Improved BLAS/LAPACK detection; new --with-blas and --with-lapack
    options to specify these libraries manually.

  * Shortened --with-hermitian-epsilon configure option to 
    --with-hermitian-eps.

  * The data-analysis tutorial is now consistent with h5topng 1.7.

  * Use new API from libctl 2.0.

MPB 1.2.2 (12/7/2001)

  * Fixed bug that caused erroneous/failed convergence when EVEN-Y/ODD-Y
    constraints were used in three dimensions.  Thanks to Rumen Iliew
    for the bug report.

  * Added convenience functions run-yeven, run-yodd, run-yeven-zeven, ...

MPB 1.2.1 (11/20/2001)

  * Fixed serious crashing bug in 1.2; thanks to Karl Koch for the bug report.

MPB 1.2 (11/15/2001)

  * Added new y-parity computation and constraints.  See the new
    run-parity function, which allows you to simultaneously specify
    the parity through the y=0 and z=0 planes, for symmetric structures.
    See also the display-yparities function.

  * z parity is no longer computed by default; see the new
    display-yparities and display-zparities functions to pass to (run).

  * Return more-accurate average epsilon, fill factor, and scalar
    epsilon values (eigenfrequencies are not affected).  Thanks
    to Mischa Megens for bugging me.

  * Now outputs D and H in consistent units (previously, D was multiplied
    by a factor of -frequency).  Thanks to Michelle Povinelli for worrying.

  * epsilon.h5 file now includes extra datasets for all components of the
    effective dielectric tensor.  (This feature is not yet supported if
    you configure --with-inv-symmetry --with-hermitian-epsilon.)

  * run-polarization is replaced by run-parity, and run-even/run-odd are
    deprecated in favor of run-zeven/run-zodd.  run-te/run-tm are now
    equivalent to run-zeven/run-zodd when invoked for 3d systems.

  * Noted new basis-size property of geometry-lattice, from libctl 1.5.
    This makes it easier to use conventional units in the fcc lattice.

  * Group-velocity computation no longer silently invalidates fields
    that have been loaded with get-dfield, etcetera.  Thanks to Marin
    Soljacic for the bug report.

  * The configure script now checks that guile is in the $PATH.  Thanks to
    Bing Li and Giridhar Malalahalli for their bug reports.

  * Rotated the W and K points of the diamond-lattice example so that
    they are oriented similarly to those in the Photonic Crystals book
    by Joannopoulos et al. (eigenfrequencies are not affected).  Thanks
    to Robert Sheldon for pointing out that this was confusing.

  * Added honey-rods.ctl example file: a 2d honeycomb lattice of rods.

  * Added line-defect.ctl example file: a line-defect waveguide in
    a 2d triangular lattice of dielectric rods, formed by a missing
    row of rods.

MPB 1.1.1 (7/4/2001)

  * Fixed bug in H-field output that caused subtly incorrect H-field
    files (only) for 3d problems when NOT using mpbi.

  * Fixed bug that caused mpbi to output incorrect results for 1d
    problems (e.g. outputted dielectric functions with zeros).

  * Changed default eigensolver tolerance from 1e-4 to 1e-7.

  * Added retrieve-gap convenience function to return the gap between
    two specified bands.

  * Fixed typo that prevented compilation of MPI (parallel) version.

  * C compiler flags -O3 are no longer used by default, since they
    don't work with some compilers; most of the performance depends
    upon the BLAS and FFTW anyway.  (Users wishing greater optimization
    can set the CFLAGS environment variable.)  Thanks to
    Giridhar Malalahalli for the bug report.

MPB 1.1 (5/6/2001)

  * Added compute-energy-integral function to make it easier to compute
    arbitrary field-energy integrals for perturbation theory; thanks to
    Marin Soljacic for the suggestion.

  * Fixed bug in output-field routines for the case of a nonzero kz
    component, that caused the fields to be multiplied by an exp(ikx)
    phase with a k in the wrong direction.  Thanks to Jesper Riishede
    for the bug report.

MPB 1.0 (2/23/2001)

  * At long last, support for distributed-memory parallel machines
    with MPI.  The computation time (and memory usage) can often improve
    nearly linearly with the number of processors.  Thanks to
    Clarendon Photonics for funding this work.

  * Also added mpb-split script to parallelize in a simpler way, without
    MPI, on e.g. SMP machines, by dividing up the list of k-points
    among a number of serial mpb processes.

  * Fixed bug in mpbi where artifacts could be introduced in 3d field
    and dielectric-function output files.  (This only affected the
    output files, not the frequency eigenvalues, etcetera.)  Thanks
    to Michelle Povinelli for the bug report.

  * Added new material-function material type, so that you can now
    specify that the dielectric tensor be an arbitrary function of
    position.  Thanks to Peter Bermel for needing this.

  * If MPB is configured with the flag --with-hermitian-epsilon, then
    complex-hermitian dielectric tensors (corresponding to magnetic
    materials, which break time-reversal symmetry) are supported.
    Thanks to Shanhui Fan for pestering me about this.